Mold and the process of making same



Patented 'Oct. 3, 1933 i MoLn AND THE PROCESS. 0.1 1

SAME

James F. Walsh, South Orange, and Bjorn Andersen, Newark, N. J., assig'nors to Cellu-' loid Corporation, a corporation of New Jersey NoDrawing. Application January 11, 1930 Serial No. 420,158

10 Claims.

This invention pertains to the general class of molds and particularly to the class of molds adapted for use with cellulosic plastics.

5 to many uses and can be readily formed and shaped by means of heat and pressure, such as in a mold. Molds used for this purpose heretofore have been of relatively high cost and have been difficult to manufacture inasmuch as same are 10 generally formed from solid masses of steel.

' Inasmuch as cellulosic plastics flow readily under heat and pressure, molds having the strength of those cut fromsolid masses of steel are not required.

An object of our invention therefore is to provide novel means for making molds.

A further object of our invention is to provide a novel mold.

A further object of our invention is to provide a novel mold that may be readily and quickly 4 manufactured; that is sufficiently strong for use in molding'thermoplastics; that is of low cost, and otherwise highly satisfactory for its intended purpose.

Further objects and advantages will become apparent to persons skilled in the art as the specification proceeds.

Our invention comprises forming a mold by building up a metallic coating applied in the form of spray, around a suitable form. This form has a configuration such that after a coating of the desired thickness has been applied, a

matrix of the proper shape and configuration results. For instance, depressions in the form are made sufficiently wider and deeper such that when the proper thicknesses of metal have been same with the proper thickness of fused metallic spray. 1

Forms for this purpose'are readily made from cellulosic plastics which may be readily formed to shape by cutting, turning, planing, molding,

or otherwise fabricating. Of the cellulosic plastics, we prefer those made with'cellulose nitrate and/or cellulose acetate, and particularly cellulose acetate. However, this invention includes the use of plastics made with cellulose formate,

cellulose'butyrate; cellulose propionate, ethyl cellulose, methyl cellulose, benzyl cellulose, cellulosephthalate, viscose, casein, etc. The manufacture of plastics with these basic materials As is well known, cellulosic plastics are adapted is known in the art and does not constitute a part of this invention.

Cellulosic plastic forms are preferably roughened, for instance with a sand blast which roughening causes the fused metal to adhere to the plastic. We also prefer to start with metals of low melting point such as tin, pewter, zinc, etc. and end up with-metals of high melting point i 12 such as copper, brass, bronze, iron, steel, etc. The use of the word metal herein includes alloys of metals.

The final matrix may be further polished or finished by any means known in the art.

While any means for applying fused metallic spray to the'form may be employed and be within the spirit of our invention, we have successfully made molds by the use of a fused metallic spray formed by passing a metallic rod longitudinally into an oxy-acetylene flame and blowing the fused metal against the form. V

Molds may thus be quickly formed; may be of any desired configuration; are strong, durable,

long-lasting, and otherwise highly satisfactory in' i the cellulosic plastic art.

Having described our invention it is obvious that many modifications may be made in the same within the scope of the claims without de- 5 parting from the spirit of the invention.

We claim:

1. The process of making molds comprising spraying a coating of metal having a low melting point on a suitable form and then spraying a 99 coating of metal having a high melting point on said first coating.

2. The process of making molds comprising spraying a coating of metal having a low melting point on a cellulosic plastic form and thenspraying a coating of metal having a high melting point on said first coating.

3. The process of making molds comprising spraying a coating of metal having a low melting point on a cellulose acetate plastic form and then spraying a coating of metal having a high melting point on said first coating.

4. The process of making molds comprising spraying a coating of tin on a suitable form and then spraying a coating of copper on said first 1 coating.

5. The process of making molds comprising spraying a coating of tin on a cellulosic plastic form and then spraying a coating of copper on said first coating.

6. The process of making molds comprising spraying a coating of tin on a cellulose acetate plastic form and then spraying a coating of cop- 7 per on said first coating.

7. A,mold. comprising a cellulosic plastic form having a sprayed metal coating thereon.

8. A mold comprising a cellulose acetate plastic form having a sprayed metal coating thereon,

9. A mold comprising a suitable form having 0 a metallic coating thereon, said. coating. compnis; Y

per;

JAMES F. WALSH. BJORN ANDERSEN. 

